Increasing Impacts of Winter Storms: A persistent Trend or a Temporary Anomaly in a Warming World?

Two of the three most damaging and deadly winter storms in modern history have been in the 2020s. The Historic 2021 Texas Freeze and winter storm caused $27B dollars and 262 direct fatalities - more than doubling the inflation-adjusted cost of the 'Storm of the Century' that occurred in March 1993. The next year the December 2022 Holiday Storm crossed the nation with devastating and deadly impacts, particularly in the Buffalo metro area. Embedded within the warmest winter in history over the CONUS, January 2024 saw over 60 direct fatalities and nearly $4B in damages from two major winter storms. This raises the question - as the climate warms, and perhaps the frequency of winter storms wanes, and our operational predictions are the best in history, how are winter storm impacts increasing?

Hypotheses of the answer to this question run the gamut. Perhaps winter storm events that do occur are indeed more intense? In fact, the 5th National Climate Assessment finds, "Over the past three decades, heavy snowfalls have been more frequent over the Northeast, a trend consistent with warming in the western Atlantic Ocean and increasingly frequent Arctic air outbreaks from polar vortex disruptions." However, in the last 3 years, this same geographic area has experienced an historic snow drought - perhaps evidence that this signal is being overwhelmed by further warming (more ‘cold rain’ storms)?

Another leading idea is that there is simply more infrastructure to damage, and that the infrastructure and systems we have are optimized with little room for error, so disruptions have an outsized impact. Or is there simply more thorough reporting of impacts? Social preparedness is another potential factor, with perhaps the public 'lulled' into a false sense of safety with quiescent periods, interrupted by what used to be 'normal' winter weather? Or are winter storms trending towards modes of more damaging ice and wind events?

This presentation will review the available evidence to date, with intention to provoke debate and motivate the session topic in general.